this is a vintage skirt that was purchased on etsy. it's circa1970s i believe.i wanted to make something using a similar crochet technique but don't understand how this is built. mostly how the crochet parts work around each leather piece but then connect so seamlessly.

does anyone have any idea on this type of crochet technique or what kind of crochet stitches they are?

This reminds me very much of a way of joining granny squares as you make them with single crochets rather than sewing them together. Perhaps you could look that up and see if it looks like the pattern?